830
FNCA52 TJSJ 120849
FWFSJU
FIRE WEATHER PLANNING FORECAST FOR PUERTO RICO
NATIONAL WEATHER SERVICE SAN JUAN PR
449 AM AST SAT SEP 12 2026
DISCUSSION
THE KBDI REMAINS HIGH ACROSS THE SOUTHWESTERN COASTAL PLAINS OF
PR, WITH THE GUANICA AND CABO ROJO RAWS REPORTING 779 AND 786,
RESPECTIVELY. WINDS TODAY WILL PREVAIL FROM THE ENE AROUND 15 MPH.
HOWEVER, SEA BREEZE VARIATIONS ARE EXPECTED ALONG THE SOUTHERN
COAST OF PR. AN OVERALL DRIER AIR MASS WITH HIGH CONCENTRATIONS OF
SAHARAN DUST WILL CONTINUE OVER THE ISLANDS TODAY. HAVING SAID
THAT, THE ENE STEERING WINDS ARE EXPECTED TO SHIFT THE FOCUS OF
SHALLOW AFTERNOON CONVECTION OVER SOUTHWESTERN PR, AND RH'S SHOULD
REMAIN JUST ABOVE CRITICAL FIRE WEATHER LEVELS. THEREFORE, A LOW
FIRE DANGER RISK IS EXPECTED IN GENERAL, WITH ISOLATED AREAS
HAVING A SLIGHTLY HIGHER RISK, PARTICULARLY ALONG THE SOUTH-
CENTRAL COASTAL PLAINS.
PRZ014-122045-
SOUTHEAST COASTAL PLAINS-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 0 0 10
TEMP (24H TREND) 93 (+3) 76 (-2) 93
RH % (24H TREND) 50 (-13) 86 (+1) 44
WIND 20FT/EARLY(MPH) E 17 NE 13 E 18
WIND 20FT/LATE(MPH) E 18 NE 11 E 19
MIXING HGT(FT-AGL/MSL)5440 5870
TRANSPORT WND (MPH) E 18 E 17
VENT RATE (KT-FT) 87040 88050
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ015-122045-
SOUTHERN HILLS-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 10 30
TEMP (24H TREND) 91 (+5) 72 (-3) 90
RH % (24H TREND) 54 (-12) 95 (+4) 56
WIND 20FT/EARLY(MPH) E 13 NE 13 E 13
WIND 20FT/LATE(MPH) E 13 NE 12 E 14
MIXING HGT(FT-AGL/MSL)5880 6340
TRANSPORT WND (MPH) E 17 E 16
VENT RATE (KT-FT) 88200 88760
DISPERSION 5 5
DSI 6 3 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ016-122045-
NORTH COASTAL PLAINS-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 0 30 30
TEMP (24H TREND) 92 (+2) 76 (-2) 92
RH % (24H TREND) 58 (-9) 94 (+3) 59
WIND 20FT/EARLY(MPH) E 13 E 16 E 13
WIND 20FT/LATE(MPH) E 18 E 13 E 19
MIXING HGT(FT-AGL/MSL)5260 5360
TRANSPORT WND (MPH) E 17 E 16
VENT RATE (KT-FT) 78900 75040
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ017-122045-
NORTHERN HILLS-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 10 30
TEMP (24H TREND) 90 (+1) 73 (-2) 91
RH % (24H TREND) 58 (-8) 96 (+1) 60
WIND 20FT/EARLY(MPH) E 12 E 14 E 12
WIND 20FT/LATE(MPH) NE 17 E 12 E 16
MIXING HGT(FT-AGL/MSL)5510 6050
TRANSPORT WND (MPH) E 15 E 15
VENT RATE (KT-FT) 71630 78650
DISPERSION 5 5
DSI 6 5 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ018-122045-
WEST COAST-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS TSTMS
CHANCE PRECIP (%) 40 10 50
TEMP (24H TREND) 93 (+1) 73 (-2) 94
RH % (24H TREND) 58 (-8) 95 (-2) 57
WIND 20FT/EARLY(MPH) E 11 E 18 E 13
WIND 20FT/LATE(MPH) E 13 E 18 E 14
MIXING HGT(FT-AGL/MSL)5320 5690
TRANSPORT WND (MPH) E 8 E 10
VENT RATE (KT-FT) 37240 51210
DISPERSION 5 5
DSI 6 3 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ019-122045-
EASTERN INTERIOR-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 40 20
TEMP (24H TREND) 91 (+4) 73 (-3) 90
RH % (24H TREND) 56 (-11) 95 (+5) 59
WIND 20FT/EARLY(MPH) E 12 E 13 E 12
WIND 20FT/LATE(MPH) E 12 E 13 E 12
MIXING HGT(FT-AGL/MSL)5780 6800
TRANSPORT WND (MPH) E 16 E 15
VENT RATE (KT-FT) 80920 88400
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ022-122045-
LUQUILLO MOUNTAIN RANGE-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 40 20
TEMP (24H TREND) 86 (+5) 71 (-4) 86
RH % (24H TREND) 62 (-14) 98 (+5) 65
WIND 20FT/EARLY(MPH) E 11 E 10 E 11
WIND 20FT/LATE(MPH) E 11 E 10 E 11
MIXING HGT(FT-AGL/MSL)5030 5320
TRANSPORT WND (MPH) E 17 E 15
VENT RATE (KT-FT) 75450 69160
DISPERSION 5 5
DSI 6 5 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ023-122045-
CENTRAL MOUNTAIN RANGE-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR MCLEAR PCLDY
PRECIP TYPE SHOWERS NONE TSTMS
CHANCE PRECIP (%) 20 0 50
TEMP (24H TREND) 89 (+5) 69 (-3) 88
RH % (24H TREND) 59 (-8) 97 (+1) 61
WIND 20FT/EARLY(MPH) E 9 NE 12 E 10
WIND 20FT/LATE(MPH) E 12 E 11 E 10
MIXING HGT(FT-AGL/MSL)6880 6930
TRANSPORT WND (MPH) E 14 E 13
VENT RATE (KT-FT) 82560 76230
DISPERSION 5 5
DSI 6 2 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ024-122045-
CAYEY MOUNTAIN RANGE-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 30 20
TEMP (24H TREND) 87 (+4) 72 (-2) 86
RH % (24H TREND) 60 (-12) 98 (+4) 62
WIND 20FT/EARLY(MPH) E 12 NE 11 E 12
WIND 20FT/LATE(MPH) E 12 E 10 E 12
MIXING HGT(FT-AGL/MSL)5190 5940
TRANSPORT WND (MPH) E 18 E 16
VENT RATE (KT-FT) 83040 83160
DISPERSION 5 5
DSI 6 4 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ025-122045-
VIEQUES-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 30 10
TEMP (24H TREND) 91 (+3) 79 (-2) 90
RH % (24H TREND) 55 (-10) 85 (+5) 57
WIND 20FT/EARLY(MPH) E 13 NE 17 E 16
WIND 20FT/LATE(MPH) E 14 E 17 E 14
MIXING HGT(FT-AGL/MSL)4710 3820
TRANSPORT WND (MPH) E 20 E 20
VENT RATE (KT-FT) 80070 64940
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ026-122045-
CULEBRA-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR PCLDY PCLDY
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 10 30 20
TEMP (24H TREND) 92 (+4) 80 (-2) 91
RH % (24H TREND) 57 (-14) 88 (+7) 59
WIND 20FT/EARLY(MPH) E 13 E 17 E 16
WIND 20FT/LATE(MPH) E 14 E 17 E 13
MIXING HGT(FT-AGL/MSL)4590 3630
TRANSPORT WND (MPH) E 18 E 20
VENT RATE (KT-FT) 73440 61710
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
PRZ027-122045-
SOUTHWEST COASTAL PLAINS AND MONA ISLAND-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR MCLEAR MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 20 10 30
TEMP (24H TREND) 93 (+2) 75 (-2) 94
RH % (24H TREND) 52 (-11) 89 (+1) 44
WIND 20FT/EARLY(MPH) E 16 E 16 E 18
WIND 20FT/LATE(MPH) E 18 E 14 E 20
MIXING HGT(FT-AGL/MSL)5640 5980
TRANSPORT WND (MPH) E 15 E 15
VENT RATE (KT-FT) 73320 77740
DISPERSION 5 5
DSI 6 3 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
VIZ001-122045-
SAINT THOMAS AND SAINT JOHN-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER PCLDY PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 20 30 20
TEMP (24H TREND) 89 (+3) 79 (-2) 88
RH % (24H TREND) 59 (-10) 90 (+8) 62
WIND 20FT/EARLY(MPH) E 14 E 17 E 16
WIND 20FT/LATE(MPH) E 14 E 17 E 14
MIXING HGT(FT-AGL/MSL)4710 3530
TRANSPORT WND (MPH) E 21 E 21
VENT RATE (KT-FT) 84780 63540
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
VIZ002-122045-
ST CROIX-
449 AM AST SAT SEP 12 2026
TODAY TONIGHT SUN
CLOUD COVER MCLEAR PCLDY MCLEAR
PRECIP TYPE SHOWERS SHOWERS SHOWERS
CHANCE PRECIP (%) 30 30 10
TEMP (24H TREND) 90 (+3) 79 (-2) 89
RH % (24H TREND) 62 (-8) 90 (+6) 63
WIND 20FT/EARLY(MPH) E 16 E 17 E 16
WIND 20FT/LATE(MPH) E 16 E 17 E 14
MIXING HGT(FT-AGL/MSL)5140 5140
TRANSPORT WND (MPH) E 22 E 18
VENT RATE (KT-FT) 97660 82240
DISPERSION 5 5
DSI 6 6 6
RH RECOVERY EXCELLENT
REMARKS...NONE.
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